Many naval shipboard power systems currently implement an alternating current (AC) power source such as a three-phase delta power source operating at 60 Hz or 400 Hz. While three-phase delta power is suitable for powering many shipboard electronic components it is not suitable for powering electronic assemblies with direct current (DC) voltage requirements.
Shipboard power systems have numerous additional requirements and constraints as a result of factors such as safety, efficiency and the noise-sensitive nature of the equipment assemblies they power. These considerations result in stringent requirements related to temperature and overcurrent protection as well as for reducing both conducted and radiated emissions. The need to operate efficiently drives an additional requirement to keep the power source balanced. In addition shipboard space limitations impose significant size-constraints on power system equipment. Finally, since replacement parts and qualified maintenance personnel are not always available shipboard power equipment must be designed to be both reliable and easy to maintain.
Existing systems capable of powering DC voltage components from an AC power source suffer various disadvantages making them unsuitable for shipboard operations.
For example, Tighe et al. (U.S. Pat. No. 5,003,453) provides a system for powering DC components based on a three-phase power source. However, the power supply of Tighe et al. is configured to output DC power converted from a three-phase wye power source. This is unlike the three-phase AC delta power sources that are commonly found on shipboard systems. In fact, the power supply of Tighe et al. would be inoperable if combined with a delta power source since, among other reasons, the power supply of Tighe et al. requires a common return or neutral which a three-phase delta power source does not have.
Thus a need exists for a power supply which is capable of converting three-phase AC power to DC power while also being suitable for shipboard installation and operation.